Gas washing and cleaning device

ABSTRACT

A gas washing and cleaning device with a vessel is partially filled with washing liquid and has an inlet for pressurized gas; a tube leads into the vessel and has its lower end disposed above the surface level of washing liquid in the vessel at variable distance, for receiving a gas-liquid droplets mixture; a baffle type separator is disposed adjacent the upper end of the tube to separate cleaned gas from liquid; a conical stopper, preferably with a 15.degree. apex angle, is disposed adjacent the lower end of the tube, partially projecting into the tube and defining therewith an annular gap of variable width for outflow of the gas-droplet mixture from the vessel; the stopper can be lifted and lowered to obtain variation in the width of the gap.

United States Patent 1191 111 3,876,398 Leisegang 5] Apr. 8, 1975 [5 GAS WASHING AND CLEANING DEVICE 3.517.485 6/1970 Dell Agnese et al. 55/227 x i 3, 26, l 7 [761 Invenm Leisegang 32 331333- 1 iii d 261/119 R Berlin 12, Germany FOREIGN PATENTS OR APPLICATIONS 4 [221 Med Jan 197 343,071 9/1936 Italy 55/248 [21] Appl. N0.: 435,412

Primary ExaminerBernard Nozick [30] Foreign Application priority Data Attorney, Agent, or Firm-Ralf l-I. Siegemund Jan. 16, 1973 Germany 2302464 ABSTRACT [52] US. Cl. 55/226; 55/239; 55/248; A gas washing and Cleaning devicg with a vessel is Pap 55/411; 261/62; 261/119 R tially filled with washing liquid and has an inlet for [5 I] Int. Cl B0ld 47/02 pressurized a tube leads into the vessel and has its Fleld of Search 55/165 lower end disposed above the surface level of washing 55/218-2191 248-249 41 1-412; liquid in the vessel at variable distance, for receiving a 261/62 119 gas-liquid droplets mixture; a baffle type separator is disposed adjacent the upper end of the tube to sepa- I References Cted rate cleaned gas from liquid; a conical stopper, prefer- UNITED STATES PATENTS ably with a 15 apex angle, is disposed adjacent the 912,167 2 1909 Potter 55/230 x lower end of the tube- Partially Projecting into the 2.027.636 1/1936 DeBolt.... 55/412 X tube and defining therewith an annular gap of variable 2,621,754 12/1952 Doyle 261/119 R X width for outflow of the gas-droplet mixture from the 2.638.1 5/1953 G on 55/412 X vessel; the stopper can be lifted and lowered to obtain 3,199,267 8/1965 Hausberg 55/257 X variation in the width of the gap 3,386,229 6/1968 Reed 261/119 R UX 3,411,271 11/1968 Gustavsson 55/226 3 Claims, 4 Drawing Figures TUBE raw-Ma PATENTEUAPR 9 5 3,876,398 sum2p 2 GAS WASHING AND CLEANING DEVICE BACKGROUND OF THE INVENTION The present invention relates to a wet washing and cleaning device for gases having a vessel partially filled with washing liquid and provided with means for charging the vessel with dust containing gas.

Washing and cleaning devices of this type are known. They include, furthermore, a tube passing into the vessel and terminating therein bu't above the surface level of the liquid. The "tube picks up the gas as forced into the vessel but mixed with liquid droplets. The upper end of the tube faces a separator baffle. Moreover, the particular tube can be constructed as a venturi pipe.

The performance and throughput of such a device is determined by the energy expended for washing. This follows from the fact that on the one hand the velocity of the gas introduced into the device is one parameter of intensity of washing, while the amount of liquid-carried along by the introduced flow of gas is another parameter, but that again depends also on the gas velocity. The washing energy/intensity is, therefore, hardly subject to control except through changing the gas pressure, but that in turn effects directly the throughput. Therefore, washing intensity of the known equip ment is not adjustable independently from throughput.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a washing and cleaning device for gas having basically the construction as outlined above, but permitting control and adjustment of the intensity of washing, for example, in dependence upon the condition of the gas to be cleaned, but for constant throughput.

In accordance with the preferred embodiment of the invention, it is suggested to improve a gas washing and cleaning device having a vessel and a tube projecting into the vessel above the surface level of washing liquid therein and having a baffie for separating gas and liquid at the outer and upper end of the tube. The specific improvement is comprised of a conical stopper which can be lifted and lowered in relation to the lower end of the tube. Moreover, the distance of the lower tube end from the liquid level is adjustable.

The conical stopper establishes an annular gap between the stopper itself and the tube end, and this gap is adjustable through lifting and lowering of the stopper. As a consequence, the velocity of the gas leaving the vessel and to be washed and cleaned can be adjusted by adjusting the width of the annular gaps without modifying gas pressure and throughput. The adjust ment covers in fact a rather large range, including velocities as used in high performance venturi washing devices.

As a consequence of the inventive features, one can adjust the washing energy and intensity in a rather welldefined manner so as to obtain optimum cleaning under various conditions. These conditions may include variations in gas volume and pressure, and the said gap and distance adjustment compensates such variations in as much as they affect optimum cleaning and washing.

In accordance with a specific feature of the invention, the apex angle of the conical stopper may be about It was found that such an angle changes the actual flow conditions very little, when the stopper is lifted or lowered in relation to the tubes exit.

DESCRIPTION or THE DRAWINGS.

While the specification concludes with claims .particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed that the invention, the objects and features ofthe invention and further objects, features and advantages thereof will be better understood from the following description taken in connection withthe accompanying drawings in which: i I I 1 FIG. 1 is a schematic view ofa washing and cleaning device in accordance with thepreferred embodiment of the invention; 1

FIG. 2 is a schematic view of a modified separation baffle; l i i FIG. 3 is a top view of the separation b'affle of FIG. 2; and I V FIG. 4 shows a modified stopper-tube assembly for use in an otherwise unmodified device as shown in FIG. 1.

Proceeding now to the detailed description of the drawings, FIG. 1 shows a cylindrical vessel 2, into which gas is fed via inlet 1. The gas is distributed around a tube 3 and leaves the interior of the vessel through the lower end 3a of the tube. That lowerend is located a certain distance above the surfacelevel 6a of a washing liquid 6a in the vessel.

A conical stopper 4 is provided at the lower end of tube 3 and projects partially into the interior of the tube thereby establishing an annular gap, through which the gas leaves the vessel in an up direction.

As gas is forced into the vessel, droplets are torn out of the liquid, actually atomizing liquid in a more or less fine spray, and the gas carries these fine droplets along as it leaves the vessel through tube 3. The atomization is in effect a rather intensive exchange of momentum as'between gas and liquid, because any liquid increment still in the vessel has zero velocity just prior to local gas stream impact. The gas is cleaned by the operation of the intensive mixing of gas and liquid droplets.

A separate baffle system 5 is provided opposite the 'upper the end of tube 3, which system'includes plural baffle plates. The gas plus liquid droplets mixture as leaving the vessel through tube 3 flows therein in updirection and impacts against the baffles; the liquid droplets are separated from the stream by mass (inertia) forces. Gas leaves the baffle chamber 5a through opening and outlet 7, while the separated liquid runs through a pipe 8 back into the sump of liquid 6.

One does not need any pumps or other conveyor systems; in the essence, the entire flow is maintained by kinetic energy of the gas as forced into the vessel.

FIG. 1 shows specifically a cylindrical tube 3 with conical stopper and one can readily see that lowering and lifting of the stopper changes the annular, crosssectional area for passage of gas plus liquid droplets into tube 3. The lifting and lowering device may be comprised of a threaded spindle 4a, threadedly received in a bore in the bottom of vessel 6 so that the lower end of spindle 4a is externally accessible for lowering and lifting the stopper. There must be, of course, a liquid seal interposed.

FIG. 4 shows a somewhat modified version with a conical or flared lower end 3' of matching angle in relation to the stopper cone 4'. The flow path control is more accurate in that manner. Lowering and lifting of the stopper can be carried out analogously as explained a tube in the vessel and having its lower end disposed with reference to FIG. 1. adjacent and above the surface level of washing liq- The ratio of liquid to gas (air), for a given gap width uid in the vessel and joined to the vessel by a wall as between stopper and tube end, is determined primarfor receiving the gas-liquid droplets mixture as proily by the distance of tube end 3a from surface level 6a. duced as an upflow therein; One can either lift or lower the tube or one can lift or a baffle type separator adjacent and positioned above lower the liquid level or one can use a combination. In the upper end of the tube to separate cleaned gas either case, the distance 3a-6a is varied, and that in from liquid droplets, there being means connected turn changes the amount of droplets carried away by to the wall for returning the separated droplets as the gas flow, (for a given operating pressure of the sys- 1Q liquid to the washing liquid in the vessel and outtem). For example, tube 3 may have a threaded portion side of the upflow in said tube; a movably adjustand is threadedly received in the top wall of vessel 2 unable conical stopper disposed adjacent the lower. derneath the baffle arrangement. Through external maend of the tube, partially projecting into the tube nipulation and transmission gearing or the like, one can and defining therewith an annular gap of variable turn the tube and lower it or raise it as needed as indi width for outflow of the gas-droplet mixture from cated by block 9. the vesseland into the tube; 1

FIG. 2 and 3 show modified baffle arrangement, 5, means for lifting and lowering the stopper to obtain which can be used in conjunction with the invention. variation in the width of said gap for obtaining ad- The invention is not limited to the embodiments dejustment of the velocity of the gas-droplet mixture scribed above but all I changes and modifications as entering the tube; and thereof not constituting departures from the spirit and means for varying the distance between the surface scope of the invention are intended to be included. level of the liquid and the lower end of the tube I claim: without changing said gap width for obtaining a de- 1. Gas washing and cleaning device comprising a vessired ratio of liquid to gas in the mixture. sel partially filled with washing liquid; 2. Device as in claim 1, wherein the conical stopper an inlet into the vessel for pressurized gas to be has an apex angle of about 15.

cleaned, in that gas under pressure tears droplets 3. Device as in claim 1, the means for varying includfrom the washing liquid to obtain a mixture of liqing means for lifting or lowering the tube in the vessel. uid droplets and gas whereby the gas is cleaned; 

1. Gas washing and cleaning device comprising a vessel partially filled with washing liquid; an inlet into the vessel for pressurized gas to be cleaned, in that gas under pressure tears droplets from the washing liquid to obtain a mixture of liquid droplets and gas whereby the gas is cleaned; a tube in the vessel and having its lower end disposed adjacent and above the surface level of washing liquid in the vessel and joined to the vessel by a wall for receiving the gas-liquid droplets mixture as produced as an upflow therein; a baffle type separator adjacent and positioned above the upper end of the tube to separate cleaned gas from liquid droplets, there being means connected to the wall for returning the separated droplets as liquid to the washing liquid in the vessel and outside of the upflow in said tube; a movably adjustable conical stopper disposed adjacent the lower end of the tube, partially projecting into the tube and defining therewith an annular gap of variable width for outflow of the gas-droplet mixture from the vessel and into the tube; means for lifting and lowering the stopper to obtain variation in the width of said gap for obtaining adjustment of the velocity of the gasdroplet mixture as entering the tube; and means for varying the distance between the surface level of the liquid and the lower end of the tube without changing said gap width for obtaining a desired ratio of liquid to gas in the mixture.
 2. Device as in claim 1, wherein the conical stopper has an apex angle of about 15.degree..
 3. Device as in claim 1, the means for varying including means for lifting or lowering the tube in the vessel. 